Cam construction



April 1940- v F. N. JACOB- 2,196,416

CAM CONSTRUCTION Original Filed Feb. 1, 1936 7 INVENTOR.

' Fesacmcx/V Jhcoa.

BY fiumfla ATTORNEY.

Patented Apr. 9, 1940 PATENT OFFICE CAM CONSTRUCTION v Frederick N.Jacob, Chicago, Ill., assignor to Johnson Laboratories, Inc., Chicago,111., a corporation of Illinois Original application February 1, 1936,Serial No. 61,874. Divided and this application July 3.

1939, Serial No. 282,725

6 Claims. (o1. 7456'7) This invention relates to an improved camconstruction adapted to operate the wire feeding mechanism of machinesfor winding electrical coils, particularly of the duolateral type andalso 5 adapted for other purposes requiring a cam having an end surfacefor effecting a variable travel of a follower member, according to theposition of the follower member on the cam, and for any position of thefollower member, providing a 10 travel thereof proportional, to theangular movement of the cam.-

The present application is a division of my copending application SerialNo. 61,874 filed February 1, 1936, for an improvement in Machines 15 forwinding duolateral electrical crils.

.My invention will be best understood by reference to the accompanyingdrawing illustrating the above and other objects thereof, in which- Fig.1 shows the cam of my invention as in- 20 cluded in coil windingmechanism in front elevation;

Fig. 2 shows'to an enlarged scale and in end elevation, the camillustrated in Fig. 1 to control the guiding of the winding wire to thecoil being 25 wound, this View being taken along the line 2-2 in Fig. 1;A

Fig. 3 shows the cam structure of Fig. 2, in side elevation; and

Figs. 4, 5, 6 and 7 are developed views of the cam surface of the camshown in Figs. 2 and 3,

at different radii of said surface, to illustrate respectively thedifferent amounts of movement of the cam follower when moving along thepaths of travel illustrated in Figs. 4 to 7 inclusive, in

35 winding coils of different axial lengths with the same cam.

Similar numerals refer to similar throughout the several views.

'As shown in Fig. l, the machine illustrated 40 includes a housing I0from the right hand end of which a base I I extends to support thewinding mechanism. The housing I0 supports a cam shaft I2 and a windingshaft I3, each in suitable bearings carried by the end walls of thehousing.

45 The winding shaft l3 carries at its right hand end, a winding spindleI I to support the core l5 of the coil [6 being wound, said core beingheld against rotation on said spindle by a thumb nut H. The com shaft I2carries on its right hand parts 5 end, a cam I8 having an end camsurface against which the left hand end of a follower rod I9 rests,which rod is supported for longitudinal, re-

ciprocating movement in bushings carried by the upwardly extending endarms 20a of a carriage 55 20.

The shafts I2 and I3 are horizontal and substantially parallel, and thefollower rod I9 is also horizontal and substantially parallel with theaxes of the shafts I2 and I3, the center line of the follower rod I9being preferably at the 5 same distance from the base II, as is thecenter line of the cam shaft I2 and. cam I8. Below the rod I9, thecarriage arms 20a support in bushings therefor, a guide rod 2|substantially parallel with the follower rod I9, said rod 2| being freeto 10, move longitudinally in its said supports. The rods I9 and 2Iextend through a yoke 22 located between the arms 20a, which yoke isrigidly secured to said rods, for example, by set screws 23. The rod I9has secured thereto between the yoke 22 and the right hand arm a, acollar 24 between which and said right hand arm, a compression spring 25is disposed around said rod, to liold said rod as far to the left as thecam I8 will permit. The end of the rod I9 adjacent the cam I8, is 20provided with an anti-friction ball 26, preferably of hardened steel, toreduce to a minimum by its rotation in the end of the rod I9, thefriction resulting from the engagement of the follower rod with therotating end surface of the cam I8. 25

The rod I9 carries between the yoke 22 and the left hand arm 20a,a'bracket 21 on a sleeve 29 and secured to said sleeve by clampingscrews 28, said sleeve being a sliding fit onthe rod and capable ofangular and longitudinal movement 30 thereon. The right handend of thesleeve 29 rests against a spacing cam 30 more fully described in saidoriginal application, which in turn rests against the yoke 22, therebeing a compression spring 3| weaker than the spring 25, around the rodI9, between the other end of said sleeve and a collar 3; secured to therod I9 by a set screw 3Ib, holding said sleeve'29 as far to the right asthe, spacing cam 30 will permit.

The bracket 21 carries an upwardly extending 40 arm 32 on the upper endof which a rotary guiding roller or equivalent wire guiding device 33 issupported, having a groove 33a to lead the winding wire 34 to the coilI6. The cam 30, the sleeve 29, the bracket 2'! and the wire guide 33thus move with the follower rod I9 and to the same extent, when thelatter is reciprocated by the cam I8.

As more clearly shown in Figs. 2 and 3, the end surface of the cam I8 ismade so its lowest point is at its outer edge at the position marked 0in Fig. 2, and its highest point is at its outer edge at the positionmarked 180 in Fig. 2. The rate of change of elevation ofthe cam surfaceis preferably proportional to the angular displacement from 0, so theintersection of the cam surface with the outer, cylindrical surface ofthe cam is helical and ascending in either direction around saidcylindrical surface, from 0 to 180. The highest point above referred to,is connected with the axis or center line of the cam, by a radial,straight line [8a of the cam surface, which line l8a is perpendicular tosaid center line, as a result of which any point in the line l8a, is ofthe same cam elevation as any other point therein. The intersection ofthe line l8a, with the center line of the cam, is the center [8b of thecam surface and is connected by an inclined straight line We with thelow point of the cam surface at 0, above referred to. The cam surface ismade up of successive straight lines extending from successive points inthe helical intersection of the cam surface with the cylindrical surfaceof the cam, to the center 18b of the cam surface. The cam surface thusproduced, affords many possible paths of travel of the follower rod 19on said cam surface, at different distances from the center l8b of thecam surface, with different total displacements of the follower rod I9axially, which are proportional to the distances of the paths from thecenter l8b, because, although the high points of said paths are the samesince they are all in the line 18a, the low points of said paths are allin the line I80, and said low point has a continuously greater elevationrelatively to the lowest point of said cam surface, as the distance ofits path of travel from the center I8?) is decreased. Furthermore, forany said path of travel, the displacement axially of the follower rod l9from instant to instant, is proportional tothe amount of angularmovement of the cam relatively to the follower I 9. The relationsdescribed are illustrated in Figs. 4, 5, 6 and 7, Fig. 4 showing indeveloped view the path of the follower rod [9 at the outer edge of thecam surface, and Figs. 5, 6 and 7 similarly showing the paths of travelindicated by the broken line circles a, b and '0 respec tively in Fig.2.

In my machine I provide means for moving the follower rod I9 across thecam surface of the cam l8, to secure any said path of travel on the camsurface, as follows: As shown in Fig. 1, the carriage 20 is mounted onthe base II in guideways 35 and 36 which are preferably horizontal andsubstantially at right angles to the axes of the shafts l2 and I3 and ofthe follower rod IS. The carriage 20 is engaged by a feed screw 31parallel with the guideways 35 and 36 and extending at its forward end,through a bracket 38 extending upwardly from the base ll, said feedscrew having a hand knob 39 secured to its outer end, and carrying acollar 40 secured to said feed screw just back of said bracket 38, saidknob and said collar preventing longitudinal movement of said feed screwthrough said bracket without interfering with rotation of said feedscrew. By rotating the feed screw 31, the carriage 20 may be movedforwardly and rearwardly across the base ll, correspondingly moving thefollower rod l9 across the cam surface of the cam l8 to secure anydesired path of travel of said follower rod on said cam surface.

While I have shown my invention in the particular embodiment abovedescribed, it will be understood that I do not limit myself .thereto, asI mayemploy ,equivalents thereof known to the art at the time of thefiling of this application, without departing from the scope of theappended claims.

Having thus described my invention, what I claim is:

1. A cam comprising a rotary body having an end cam surface, said camsurface covering the entire end surface of said body and having a highline extending from the cam axis to the outer edge of the cam surfaceand having a low line extending from the axial end of said high line tothe outer edge of said cam surface, said high line being axiallydisplaced above said low line for all radii of said cam surface, wherebythe extent of movement of the cam follower will be controlled by theextent of its radial displacement from said axis.

2. A cam comprising a rotary body having an end cam surface, said camsurface covering the entire end surface of said body and having a highline extending from the cam axis to the outer edge of the cam surfaceand having a low line extending from the axial end of said high line tothe outer edge of said cam surface, said high line being axiallydisplaced above said low line for all radii of said cam surface, theaxial displacement of said high line above said low line beingproportional to the radius of the path of follower travel on said camsurface, whereby the extent of movement of the cam follower will becontrolled by the extent of its radial displacement from said axis.

3. A cam comprising a rotary body having an end cam surface, said camsurface covering the entire end surface of said body and having a highline extending from the cam axis to the outer edge of the cam surfaceand having a low line extending from the axial end of said high line tothe outer edge of said cam surface, said high line being axiallydisplaced above said low line for all radii of said cam surface, therise from said low line at any radius of said cam surface beingproportional to the angular displacement from said low line, whereby theextent of movement of the cam follower will be controlled by the extentof its radial displacement from said axis.

4. A cam comprising a rotary body having an end cam surface, said camsurface covering the entire end surface of said body and having a highline extending at right angles from the I cam axis to the outer'edge ofthe cam surface and having a low line extending from the axial end ofsaid high line to the outer edge of said cam surface, said high linebeingaxially displaced above said low line for all radii of said camsurface, the axial displacement of said high line above said low linebeing proportional to the radius of the path of follower travel on saidcam surface, and the rise from said low line at any radius of said camsurface being proportional to the angular displacement from said lowline, whereby the extent of movement of the cam follower will becontrolled by the extent of its radial displacement from said axis.

5. A cam comprising a cylindrical body having an end cam surface, saidcam surface extending over the entire end surface of said body andhaving a form produced bypassing a surface-generating straight linethrough a fixed point in the axis of said body and with said generatingline always containing said fixed point moving said generating lineangularly along the path of a closed curve on the cylindrical surface ofsaid body, said closed curve comprising two reversed helical curves.

6. A cam comprising a cylindrical body having an end cam surface, saidcam surface extending over the entire end surface of said body andhaving a form produced by passing a surface-generating straight linethrough a. fixed point in the axis of said body and with said generating line always containing said fixed point movingsaid generatingline angularly along the path of a closed curve on the cylindricalsurface of said body, said closed curve comprisingtwo reversed helicalcurves, said helical curves being similar and of equal length.

FREDERICK N. Jacoa

